Premiere Pro CS4 CONSTANTLY crashing

I'm losing my mind. This program is constantly crashing while editing during a host of functions: rendering, trimming, titling - you name it. I'm under the gun here and I'm going crazy. Please help me make this system more stable:

Premiere Pro CS4
Windows XP Pro V.2002
SP3
Dell Precision PWS 690 Quad Core
Intel Xeon CPU
E5320 @ 1.86Ghz
1.86 Ghz, 3.00 GB Ram

Thanks in advance. Dyin ovah heah.

HDV 1080i NTSC project
1/2 hour TV show. Close to 700 clips.
Dell Precision 690 Tower / Quad core. 4g Ram / @ 1.86Ghz

I've tweaked everything I know how to tweak and the problem seems to be isolated to rendering at this point. I have my RAM maxed out. I defrag frequently.

I have all of my footage, etc. on one internal drive. I have all of my previews going to another internal drive. Nothing going to the C drive and nothing going to a fourth internal drive.

Is this a scratch disc issue? How should they be set up?

What else could be causing this? It's killing me.

If I'm running 32 bit XP I can't be working at 64 can I? No programs running in the background. Just crashed (hard) again. Third time this afternoon. Each time was during a render.